Parliamentary Party Instability and Party System Evolution

• In Event: The Development of Parties and Party Systems

Abstract

How does party instability in parliaments affect the long-term development of political parties and party systems? While party switching carries the potential to affect political stability in general, the two topics are often studied in isolation. On the one hand, the literature on party systems tends to focus on parties as organizational entities and on electoral change, rather than on the actions of individual MPs during an electoral term. On the other hand, studies on parliamentary instability (party switching) focus on the behaviour of individuals and/or parliamentary groups and pay limited attention to how this affects the development of parties and party systems beyond a parliamentary term.

This paper bridges this gap by analyzing how parliamentary change affects party systems. Specifically, we examine how different types of instability (defections vs. exits, collective vs. individual switches) affect the composition of slates (i.e. candidate lists of "electoral parties") at both the gaining and losing ends of MPs. We examine four European democracies with volatile party systems and frequent parliamentary switches (Italy, Lithuania, Poland, and Romania) over a period of two decades. We analyse the effects of party instability on the levels of candidate return and dropout (beyond switching MPs), and whether lost candidates are replaced by newcomers or by the promotion of previous candidates. In addition, we consider party performance both at the national level and in the districts affected by switching. We demonstrate that some types of parliamentary instability have a more profound effect on party system evolution than others.

Authors

• Allan Sikk, University College London

• Sona N. Golder, Penn State University

• Raimondas Ibenskas, University of Bergen

• Paulina Salek-Lipcean, University College London